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Think globally, act locally - the reality in a landfill gas project in Iceland
Metan
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Figure 1. Landfill site, new upgrading plant (designed by VGK Consulting and built by local craftsmen) and new NGV bus and waste truck |
Technologies to reduce greenhouse gas emissions (GGE) are being sought out
the world over, both small and large-scale projects - they need not be big to
be valued and counted in the effort to reduce emissions. A small-scale landfill
project in Iceland plays a vital role in feeding the increasing demand for green
energy there. It produces clean energy to run bi-fuel cars or dedicated Natural Gas
Vehicles (NGVs).
Landfills are an inevitable part of both modern and ancient life and remains of
human activity can be found worldwide. They range in size and also content which
depends on local conditions. The biggest site in Iceland is located on the outskirts
of Reykjavík in Álfsnes, and serves the 180,000 people in the greater capital area.
This landfill (Figure 1) has been in operation since 1991 and uses a unique method
where the waste is baled before landfilling.
In the early years the gas emitted was flared off, but 1996 it started to be
collected. Normally the gas can be used for district heating and electricity
production. In Iceland, however, 100% of electricity is either produced by
hydropower or geothermal energy and 90% of houses are heated with geothermal
energy, the rest mainly with electricity. So other uses were sought and found in
vehicle fuel as all transportation fuel is imported to Iceland.
As a result there are now 50 vehicles that are either bi-fuel or dedicated Natural
Gas Vehicle (NGVs), including two city buses, one waste truck and one
container truck.
A water scrubber pilot plant - to remove contaminants from the gas - was built
in 2000. Methods other than water scrubbing were examined and discarded as
too expensive. At the same time some 20 bi-fuel smaller vehicles were imported,
which can run on the upgraded landfill gas (methane) or gasoline.
Since 2000, development has been steady. Design of a new water scrubber
upgrading plant began in 2004 and was installed by 2005 to meet the increased
demand. With special packing material in the scrubbing tower, much lower towers,
and efficient use of water, removal of CO2 is up to 100%. This plant (Figure 1) is designed by a local Engineering company (VGK Engineering), experienced people
from the landfill owner (SORPA BS) and with input from SWECO AB (Consulting)
in Sweden.
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Figure 2. Vehicles running on upgraded landfill gas are used to promote the companies and domestic green fuel |
A pipeline from the plant to the point of delivery (10 kilometres) is projected and
work is expected to start in September this year. A further development could be to produce the gas
by fermentation. This
would make the process
more effective, instead of
collecting the gas as a byproduct
from the landfill.
According to current
plans, the Álfsnes landfill
will be in use until 2014.
However, gas generation
in harvestable quantities
will be possible until at
least 2030. If all the gas
was to be - and it clearly
can be - used as vehicle
fuel, it would provide
fuel for approximately
4,000 smaller vehicles
or about 2% of the total
vehicle fleet in Iceland,
thus saving further on
GGE from the local
traffic. Figure 2 shows
how upgraded methane
can be used on the range
of smaller personal cars,
trucks and dedicated
NGVs.
Even though this is a
small project, in comparison to international GGE issues, it responds to the UN
environmental agenda: “Think globally, act locally”! It is one of the few plants
using landfill gas for transportation fuel. Worldwide using landfill gas could be an
inexpensive way of reducing emissions and, furthermore, small local sources can
also increase fuel security.
Partners in this project are SORPA (Capital area waste management company),
ESSO in Iceland, OR (Reykjavik Energy Company), NSA (Private Investment Fund)
and Metan Ltd. VGK Engineering Ltd has provided design and engineering services.
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